Converter type vessels of the Q-BOP and BOF types generally include a pear-shaped vessel open at its upper end to receive a metallic charge. Such vessels are normally mounted on a trunnion ring having trunnion pins supported by bearings for pivotal movement about a generally horizontal axis. The drive for pivoting vessels of this type typically includes a bull gear mounted on one of the trunnion pins and coupled by pinion gears to one or more drive motors. Such trunnion ring pinion supports are relatively complicated and expensive to fabricate and maintain.
Converter vessels of the Q-BOP type commonly include a removable bottom having a plurality of oxygen tuyere pipes each of which is surrounded by a second pipe for injecting a hydrocarbon shielding fluid in surrounding relation to the oxygen for the purpose of prolonging the life of the tuyeres and the surrounding refractory material. Notwithstanding the use of hydrocarbon shielding fluid, however, the bottom refractories and tuyeres wear at a substantially faster rate than the refractory material in the remaining portions of the vessel. For this reason, it is necessary to periodically replace Q-BOP vessel bottoms and their associated tuyeres several times during the life of the refractory in the upper portion of the vessel. The replacement of Q-BOP vessel bottoms requires that the vessel be out of service for substantial periods of time.
The treatment of ferrous metal in Q-BOP vessels not only involves the delivery of oxygen and a hydrocarbon shielding fluid but other gases such as, for example, nitrogen, air and argon and solid materials such as lime, burnt lime, fluorspar, carbon, iron oxide and the like. The solid materials are commonly entrained in nitrogen, argon or the oxygen and delivered through the oxygen tuyere pipe. Because of the tendency of such powdered material to coat the lining of the gas delivery system, the use of readily oxidizable desulfurizing agents such as calcium and magnesium is precluded.